Option A is correct. Air stress waves undergo conversion to fluid pressure waves in the middle ear. Then conversion of fluid pressure into nerve impulses takes location in the inner ear. Thus, direct conversion of air stress waves to nerve impulses does now not appear however via fluid strain conversion.
Bending of greater stereocilia underneath the influence of a sound wave reasons mechanical opening of the mechanoelectrical transducer (MET) channels on the membranes of decrease stereocilia by way of tensioning the tip of every lower stereocilium with the facet wall of its associated greater one.
The Eustachian tube, which opens into the center ear, is responsible for equalizing the stress between the air outdoor the ear and that inside the center ear.
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